Sum all values in every column of a data.frame in R

Question

Given this data set:

  Name Height Weight 1 Mary     65    110 2 John     70    200 3 Jane     64    115 

I'd like to sum every qualifier columns (Height and Weight) yielding

 199  425 

The problem is that the qualifiers can be more than just 2 (i.e. more than just Height and Weight).

I can do this.

    # Create the dataframe people     Name <- c("Mary", "John", "Jane")     Height <- c(65,70,64)     Weight <- c(110,200,115)     people <- data.frame(Name, Height, Weight)      res <- c(sum(people$Height),sum(people$Weight)) 

But it gets too long when the qualifier increase. What's the compact way to do it?

Answer 1

You can use function colSums() to calculate sum of all values. [,-1] ensures that first column with names of people is excluded.

 colSums(people[,-1]) Height Weight     199    425 

Assuming there could be multiple columns that are not numeric, or that your column order is not fixed, a more general approach would be:

colSums(Filter(is.numeric, people))